2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane | CAS 2086689-05-4

2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane is a PEG-based azide functional building block designed for copper-free and copper-mediated azide–alkyne click chemistry workflows. The molecule combines an azide handle with a short, flexible PEG3 spacer and two carboxylate groups, enabling both efficient conjugation and strong water-phase compatibility. Its amphiphilic, multi-functional structure makes it well-suited for constructing well-defined, soluble bioconjugates and labeled materials used across chemical biology, molecular imaging, and diagnostic reagent development.

1. Antibody And Protein Labeling

2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane is commonly used as an azide-bearing linker to introduce click-reactive functionality onto proteins and antibody derivatives prior to downstream conjugation with alkyne-functional probes. The PEG3 segment helps maintain colloidal stability and reduces nonspecific aggregation during labeling, while the carboxylate groups support robust coupling strategies for preparing defined conjugation intermediates. Researchers use this reagent to generate site-specific or semi-defined protein conjugates for assay development, imaging reagent screening, and workflow-compatible probe assembly.

2. Cell Surface And Biomolecular Tagging

2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane is useful in chemical biology studies where azide handles are installed on biomolecules or biomolecule-adjacent constructs to enable subsequent click attachment of fluorophores, affinity tags, or imaging moieties. The presence of PEG3 improves dispersion in aqueous buffers and can help preserve biomolecular accessibility during conjugation steps. In practical labeling workflows, the two carboxylate groups offer additional anchoring or intermediate formation options, supporting the preparation of soluble tagging reagents used for tracking biomolecular interactions and mapping biomolecular assemblies.

3. Molecular Imaging Probe Construction

2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane is widely adopted as a click-ready scaffold for assembling imaging probes that require water-soluble, spacer-containing linkers between a targeting or reporting group and the final imaging handle. The azide functionality allows modular coupling to alkyne-bearing dyes, reporters, or imaging-compatible motifs, while the PEG3 spacer helps tune hydrophilicity and reduce steric constraints that can limit labeling efficiency. Carboxylate groups further enable intermediate derivatization or coordination to material surfaces, supporting probe formats used in fluorescence-based imaging and molecular detection platform development.

4. Diagnostic Reagent And Assay Platforms

2-(Azido-PEG3-amido)-1,3-bis(carboxylethoxy)propane supports the fabrication of diagnostic and screening reagents where click chemistry provides a reliable route to attach detection chemistries to assay-compatible carriers. The reagent’s dual carboxylate functionality is often leveraged to prepare conjugation-ready intermediates for immobilization on activated surfaces or for building soluble assay components that maintain performance in buffered, aqueous environments. By providing a stable azide handle separated by a PEG3 spacer, it enables consistent modular assembly of labeled reagents used in research-grade immunoassays, binding assays, and multiplexed detection workflows.